Investigation on the heat dissipation of high heat flux chip array by fractal microchannel networks

With the development of integrated circuits, high power and high integration chip array devices are facing the requirements of high heat flux and temperature uniformity. The microchannel heat sink can meet the heat dissipation requirements of chip array devices with high heat flux, and the flow channel with fractal structure can achieve high temperature uniformity of chip array. In this study, the H-shaped fractal microchannel structure was proposed to cooling the 4?4 chip (1 ? 1 mm) array. The interior fillet structure (IFS) was introduced to optimize T-shaped and L-shaped corner structures in the fractal channel. The simulation results show that the overall pressure drop of microchannel heat sink with IFS is reduced 18.7%, and the maximum temperature difference of 4?4 chip array is less than 1.2?C at 1000 W/cm2. The microchannel heat sink with IFS was fabricated and assembled, and the hydro-thermal performance was characterized by thermal test chip (TTC) at different flow rates and heat fluxes. The experimental results show that the standard deviation of temperature of 4?4 chip array is less than 3.5?C at 1000 W/cm2 and 480 ml/min. The error between experimental and simulation data is within ?1.5%, which proves the reasonability of computational fluid dynamic (CFD) modeling and simulation. And furthermore, the results demonstrate that by introducing IFS into the T-shaped and L-shaped structures could reduce pumping power and improve temperature uniformity of chip array, which can be applied to improve the performance of the chip array devices with high heat flux.